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ArcticMyst Security by Avery

My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

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Oct 7, 2011
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My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

Ok so I got a wild hair up my arse the other night and decided to whip together a linear driver out of scavenged spare parts. Of all the linear drives I have seen the are all a giant clusterhump of tangled wires... you cant tell what goes where. So I decided to come up with my own layout. This is a prototype, mainly just to figure out how I was going to lay out the circuit. Everything but the breadboard, the LM317, and the terminal blocks. Later on I plan on putting a 1084 or other IC on there (I found one on there with a mere 400mv dropout... this opens the door to some interesting power possibilities. I hope to run it off of a 9v switch mode wall wart (considering I get them at the local goodwill store all the time for $2 each). So without further ado, here is what I come up with so far:

100_1029.jpg


100_1030.jpg






Basically this is your typical linear driver (minus your feedback resistors) except it has several safety features built in not included in some of the other driver designs I have seen.

The first is the green LED. Pretty much simple... dropper resistor connected to the LED. This lets you know right off if your power is connected properly... terminals reversed, no lights.

The second safety feature is the red LED. In addition to letting you know your regulator IC is getting power, it is also a "dump load". Red was specifically chosen since AFAIK, red LED's generally have the lowest forward voltage drop. So, basically as soon as you cut the power off, since it is connected across the terminals of the input filtering cap it drains the cap.

The third safety feature is the IN4001 diode. This is connected to the "IN" pin of the regulator and input filtering cap. During normal circuit operation the input voltage is greater than the output voltage so no current (well maybe other than a little bit of leakage current) flows thru it. But again, as soon as you cut the power the dump load will drain the main cap, the voltage will go down on the primary side, thus allowing current to drain out of the output filter cap potentially saving your laser diode.

I hope I have covered all my bases with this one. I have tried to keep the feedback and filtering caps as close to the applicable components as possible. And yes I will transfer the whole setup to a brand new breadboard prior to testing and use all new components... the breadboard it is on is simply a board that I use to practice my layouts on.

But I still have some questions... how much input and output capacitance is necessary I'm using ultra low ESR capacitors with high ripple current ratings, are tantalums necessary? Currently have 100uf on input filter and 47uf on output, is this overkill or could it handle more? I like the whole idear of having a "soft start" driver.

Wish I had a scope. :cryyy:
 
Last edited:





Joined
Sep 20, 2008
Messages
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Points
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Re: My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

Ok so I got a wild hair up my arse the other night and decided to whip together a linear driver out of scavenged spare parts. Of all the linear drives I have seen the are all a giant clusterhump of tangled wires... you cant tell what goes where. So I decided to come up with my own layout. This is a prototype, mainly just to figure out how I was going to lay out the circuit. Everything but the breadboard, the LM317, and the terminal blocks. Later on I plan on putting a 1084 or other IC on there (I found one on there with a mere 400mv dropout... this opens the door to some interesting power possibilities. I hope to run it off of a 9v switch mode wall wart (considering I get them at the local goodwill store all the time for $2 each). So without further ado, here is what I come up with so far:

100_1029.jpg


100_1030.jpg






Basically this is your typical linear driver (minus your feedback resistors) except it has several safety features built in not included in some of the other driver designs I have seen.

The first is the green LED. Pretty much simple... dropper resistor connected to the LED. This lets you know right off if your power is connected properly... terminals reversed, no lights.

The second safety feature is the red LED. In addition to letting you know your regulator IC is getting power, it is also a "dump load". Red was specifically chosen since AFAIK, red LED's generally have the lowest forward voltage drop. So, basically as soon as you cut the power off, since it is connected across the terminals of the input filtering cap it drains the cap.

The third safety feature is the IN4001 diode. This is connected to the "IN" pin of the regulator and input filtering cap. During normal circuit operation the input voltage is greater than the output voltage so no current (well maybe other than a little bit of leakage current) flows thru it. But again, as soon as you cut the power the dump load will drain the main cap, the voltage will go down on the primary side, thus allowing current to drain out of the output filter cap potentially saving your laser diode.

I hope I have covered all my bases with this one. I have tried to keep the feedback and filtering caps as close to the applicable components as possible. And yes I will transfer the whole setup to a brand new breadboard prior to testing and use all new components... the breadboard it is on is simply a board that I use to practice my layouts on.

But I still have some questions... how much input and output capacitance is necessary I'm using ultra low ESR capacitors with high ripple current ratings, are tantalums necessary? Currently have 100uf on input filter and 47uf on output, is this overkill or could it handle more? I like the whole idear of having a "soft start" driver.

Wish I had a scope. :cryyy:

I see one major problem with your Breadboard Driver design....

The required Adjust Pin of the LM317 is NOT connected to anything....:thinking:

Is your circuit supposed to be a Voltage Regulated Linear Driver or
a Current Regulated Linear Driver...:thinking:

Have you tested that circuit....:thinking:
Feedback resistors are required for an LM317 adjustable Regulator...



Jerry
 
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Joined
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Re: My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

To directly answer the title question,

What I think is, it's no prototype driver. It's a simple circuit made from schematics which people have drawn and which was built million times before. There is no novelty to it. There even is no practicality to it, it has way too many components than actually needed. Adressing both THAT and your "Clusterhump of wires" comment, I so love posting this picture...

PA234913.jpg


Just for the record, THIS is a clusterhump of wires:
Cincilator.jpg


Note, my comments are as objective as possible, please don't be offended, and I'm sorry for uhh, "bursting your bubble", but it's really not a prototype or anything "new" if it's same everybody already uses (difference such as LED ON indicator are minor at best).

Don't get me wrong, it's nice to see people building stuff for themselves - if you do come across a new design of a circuit or new IC that can be used, THAT is a discovery needed to be shared with the forum :)
 
Joined
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Re: My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

lol :D
what exactly is that board Eudaimonium :D does it work or it's just really a clusterhump of wires and random parts :D nice one :crackup:
 

ped

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Re: My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

And id love to see the host your going to fit that breadboard into!
 
Joined
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Re: My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

I dunno what that board is, somebody posted that on LaserChat I think, I just saved the picture in my "Fun sh*t" folder. I believe I also posted it before in "Win thread" or somewhere.

Judging by the complexity and certain patten to the components and layout, it is doing something, my best guess is some sort of multi-channel audio amplifier (judging by the chinch connectors). I wouldn't say it's any more specific than that, since the more complex the circuit is, the better it becomes to just buy the finished product than build your own. Though that's just my own opinion, without precise IC markings it can literally be anything (from some sort of VU-Meter to DIY-Memory or even simple processor-like circuit).
 
Joined
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Re: My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

well whatever it is someone spent a hell lot of time making it :D
 
Joined
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Re: My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

Yeah, probably took weeks to build (and months to troubleshoot).

I always laugh at the small boards added on along the edges, indicating he RAN OUT OF SPACE on something like 2 feet by 1 foot board.

Also, there are small tags written for ICs and switches, indicating tidyness, contradictory to the board itself (should've been etched, would take small amount of space, looking a lot better).

Maybe he just really really hates drilling those 1mm holes for pins. I do but not THAT much.

I also got this one:
pict6120_2.jpg

Seriously not sure if it's fake or not.

One one hand, you've got the pins being soldered through the holes, obviously, and a few caps added on the side you can see. On the other, the wire does not appear to be insulated at all, and horizontal lines are all connected on the board already, so basically *everything* is shorted.
 
Joined
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Re: My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

wow it hurts my eyes just by looking at it :D:D
we should replicate it and see what it does, whacha say? :D:D:crackup:
 
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Re: My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

The red wire is from a motor..it is isolated by a lacquer.
And the copper lines are multiple times cut...so it looks legit :D
Btw: I'm also wondering what that biiiiiig clusterhump of wires does ;)
 
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Re: My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

i think we highjacked the thread .... :tsk::D:D
 
Joined
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Re: My prototype DIY linear breadboard driver the "Evil Drive v1.0"... whatcha think?

That board on both front a rear pics is called Vero Board.
We use it exclusively for prototype testing just before
designing PBCs...

We wire everything on the front component side only.
There is special tool that allows you to cut the copper
traces that run from one end of the board to the other
for separate circuits.

The wire in the pics is either Red insulated Wire-Wrap
wire or as regalis stated enamel insulated Magnetic Wire
used to wind coils...


Jerry
 
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